Husqvarna 445, 445e, 450e manual Working Techniques, Basic cutting technique

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Basic cutting technique

WORKING TECHNIQUES

7Take great care when you cut with the top edge of the bar, i.e. when cutting from the underside of the object. This is known as cutting on the push stroke. The chain tries to push the chain saw back towards the user. If the saw chain is jamming, the saw may be pushed back at you.

8Unless the user resists this pushing force there is a risk that the chain saw will move so far backwards that only the kickback zone of the bar is in contact with the tree, which will lead to a kickback.

Cutting with the bottom edge of the bar, i.e. from the top of the object downwards, is known as cutting on the pull stroke. In this case the chain saw pulls itself towards the tree and the front edge of the chain saw body rests naturally on the trunk when cutting. Cutting on the pull stroke gives the operator better control over the chain saw and the position of the kickback zone.

9Follow the instructions on sharpening and maintaining your bar and chain. When you replace the bar and chain use only combinations that are recommended by us. See instructions under the headings Cutting equipment and Technical data.

Basic cutting technique

WARNING! Never use a chain saw by ! holding it with one hand. A chain saw is

not safely controlled with one hand. Always have a secure, firm grip around the handles with both hands.

General

Always use full throttle when cutting!

Reduce the speed to idle after every cut (running the engine for too long at full throttle without any load, i.e. without any resistance from the chain during cutting, can lead to serious engine damage).

Cutting from above = Cutting on the pull stroke.

115 10 81-26 Rev.2 2008-01-11

Cutting from below = Cutting on the push stroke.

Cutting on the push stroke increases the risk of kickback. See instructions under the heading How to avoid kickback.

Terms

Cutting = General term for cutting through wood.

Limbing = Cutting branches off a felled tree.

Splitting = When the object you are cutting breaks off before the cut is complete.

There are five important factors you should consider before making a cut:

1Make sure the cutting equipment will not jam in the cut.

2Make sure the object you are cutting will not split.

3Make sure the chain will not strike the ground or any other object during or after cutting.

4Is there a risk of kickback?

5Do the conditions and surrounding terrain affect how safely you can stand and move about?

Two factors decide whether the chain will jam or the object that you are cutting will split: the first is how the object is supported before and after cutting, and the second is whether it is in tension.

In most cases you can avoid these problems by cutting in two stages; from the top and from the bottom.You need to support the object so that it will not trap the chain or split during cutting.

IMPORTANT! If the chain jams in the cut: stop the engine! Don’t try to pull the chain saw free. If you do you may be injured by the chain when the chain saw suddenly breaks free. Use a lever to open up the cut and free the chain saw.

The following instructions describe how to handle the commonest situations you are likely to encounter when using a chain saw.

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Contents 445 445e 450e Operator′s manualSymbols on the machine KEY TO SYMBOLSSymbols in the operator’s manual Contents CONTENTSDear Customer INTRODUCTIONWhat is what on the chain saw? WHAT IS WHAT?Before using a new chain saw GENERAL SAFETY PRECAUTIONSAlways use common sense Machine′s safety equipmentPersonal protective equipment Chain brake and front hand guard8 – English Throttle lockout Right hand guard Stop switchVibration damping system MufflerGeneral rules Cutting equipmentCutting equipment designed to reduce kickback WARNING! Departure from the General information on sharpening cutting teethsharpening instructions considerably increases the risk of kickbackincreased if the depth gauge setting is General advice on adjusting depth gauge settingAdjustment of depth gauge setting Tensioning the chain445e, 450e which could lead to serious, even fatal injuries Lubricating cutting equipmentChain oil Filling with chain oilChain drive sprocket Fitting the bar and chain ASSEMBLYFitting a spike bumper Fuel FUEL HANDLINGFuelling Fuel safetyTransport and storage Long-termstorageStarting and stopping STARTING AND STOPPINGStopping Before use WORKING TECHNIQUESGeneral working instructions 24 – English Basic cutting technique Tree felling technique 12 3Clearing the trunk and preparing your retreat Felling directionFelling Directional cutsFelling cut What is kickback? How to avoid kickbackFreeing a tree that has fallen badly Limbing WARNING! A majority of kickback Carburettor adjustment MAINTENANCEGeneral Checking the brake trigger Checking the inertia brake releaseimmediately Muffler Replacing the starter cord StarterTensioning the recoil spring Replacing the return and drive springs Air filterFitting the starter Lubricating the bar tip sprocket Spark plugNeedle bearing lubrication Cooling systemWinter use ”Air Injection” centrifugal cleaningTemperature -5Cor colder Daily maintenance Maintenance scheduleWeekly maintenance Monthly maintenanceTechnical data TECHNICAL DATASaw chain filing and file gauges Bar and chain combinationsLength, inch Pitch, inchApplies to Europe only EC-declarationof conformity´z+S,¶6c¨ ´z+S,¶6c¨ Page 1151081-26 ´z+S,¶6c¨ ´z+S,¶6c¨